Door actuation apparatus with locking mechanism for elevators

ABSTRACT

A door actuating apparatus for elevators, wherein an elevator cabin door is positively connected at the region of the floor of a building by a coupling mechanism with an elevator shaft door located at each such building floor. The elevator cabin door is movable through the agency of a thrust crank drive located in a dead-center position when the elevator cabin door is closed, such thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of a speed reduction drive. According to important aspects of the invention the coupling mechanism incorporates an entrainment parallelogram mounted at the elevator cabin door and forming the entrainment member of the coupling mechanism. An actuation mechanism serves to actuate the entrainment parallelogram. At least one pin member is secured to the elevator shaft door. The entrainment parallelogram cooperates with such pin member for the purpose of coupling the elevator shaft door with the elevator cabin door. A blocking lever is connected for movement with the entrainment parallelogram. A stop member is secured to the elevator cabin and cooperates with said blocking lever to prevent opening of the elevator cabin door when the blocking lever is located within the effective range of said stop member and permits opening of said elevator cabin door when said blocking lever is located outside of the effective range of said stop member.

United States Patent [191 Voser DOOR ACTUATION APPARATUS WITH LOCKING MECHANISM FOR ELEVATORS [75] Inventor: Albert Voser, Ebikon, Switzerland [73] Assignee: Inventio AG, l-lergiswil, Switzerland [22] Filed: Dec. 20, 1971 [21] Appl. No.2 209,826

[30] Foreign Application Priority Data Dec. 30, 1970 Switzerland 19397/70 [52] US. Cl. I87/52 [51] Int. Cl B66b 13/00 [58] Field of Search 187/51, 52 R, 52 C,

[56] References Cited UNITED STATES PATENTS 3,605,952 9/1971 Lusti l87/52X 3,065,826 11/1962 Tucker 187/52 R Primary Examiner-Evon C. Blunk Assistant Examiner-Douglas D. Watts Attorney-Werner W. Kleeman [57] ABSTRACT A door actuating apparatus for elevators, wherein an elevator cabin door is positively connected at the region of the floor of a building by a coupling mechanism with an elevator shaft door located at each such building floor. The elevator cabin door is movable through the agency of a thrust crank drive located in a dead-center position when the elevator cabin door is closed, such thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of a speed reduction drive. According to important aspects of the invention the coupling mechanism incorporates an entrainment parallelogram mounted at the elevator cabin door and forming the entrainment member of the coupling mechanism. An actuation mechanism serves to actuate the entrainment parallelogram. At least one pin member is secured to the elevator shaft door. The entrainment parallelogram cooperates with such pin member for the purpose of coupling the elevator shaft door with the elevator cabin door. A blocking lever is connected for movement with the entrainment parallelogram. A stop member is secured to the elevator cabin and cooperates with said blocking lever to prevent opening of the elevator cabin door when the blocking lever is located within the effective range of said stop member and permits opening of said elevator cabin door when said blocking lever is located outside of the effective range of said stop member.

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1 DOOR ACTUATION APPARATUS WITH LOCKING MECHANISM FOR ELEVATORS BACKGROUND OF THE INVENTION The present invention relates to a new and improved door actuation or drive apparatus equipped with a locking mechanism for use in elevators, wherein an elevator cabin door which can be positively connected with an elevator shaft door at the region of the relevant or associated floor or storey by means of a coupling mechanism, can be moved by a thrust crank drive located in a dead-center position when the door is closed, the crank wheel of which is driven by a motor arranged upon the elevator cabin through the agency of a speedreduction drive.

With a similar type prior art door actuation apparatus a double lever is rotatably arranged at the cabin door which, on the one hand, at the region of a floor engages with a coupling rail secured to the elevator shaft door and, on the other hand, is connected through the agency of a connection rod with a locking lever rotatably mounted at the cabin door. The double lever possesses at both of its ends a respective contact roller and under the weight of the locking mechanism and connection rod is retained in an inclined position when the door is closed. During opening of the door, at the locality of a floor, the one roller of the double lever initially comes to bear against the coupling rail. Thereafter, the double lever is rotated in such a fashion that both rollers are disposed vertically above one another. During this movement the cabin door is unlocked through the agency of the connection rod. After both rollers of the double lever have come to bear against the coupling rail the elevator shaft door is entrained by the elevator cabin door.

If during a defect or malfunction the elevator remains stuck between two floors of the structure or building, then, the cabin door cannot be opened by the passengers from within the cabin since the double lever, due to the absence of the coupling rail, upon moving the door is not able to rotate and such therefore remains locked. On the other hand, if upon the occurrence of a defect the cabin is already located at the region of a floor or when a defect arises is brought to such location, then, the passengers can manually open the door since in this case the coupling rail of the elevator shaft door rotates the double lever and unlocks the elevator cabin door.

This mode of operation is faultless. Yet, a disadvantage of the selected construction resides, however, in the fact that during normal operation the elevator shaft door is first opened after the elevator cabin door has already moved a considerable distance. The latter must of course initially overcome the play prevailing between the coupling rail and the double-lever rollers and then must move through a certain path of travel in order to be able to rotate the double lever and to unlock the door until it can entrain the elevator shaft door. In the case of modern day high-speed elevators or lifts with direct driving-in to the relevant floor the opening of the door is already prepared prior to the time that the elevator cabin comes to stand still in order to reduce the door opening time. This preparatory door opening operation occurs, for instance, when the elevator cabin is still spaced approximately 25 cm. from the level of the floor where it is to stop. Hence, the drive motor is switched-in and the door unlocked. Since with the described state-of-the-art door actuation or drive apparatus the unlocking operation first occurs after the cabin door already has opened by a certain amount, this apparatus is not suitable for the mentioned purposes. An accident can occur if a passenger reaches through the opening at the elevator cabin entrance in a direction towards the elevator shaft door which is moving relative to such passenger. A further drawback of this construction resides in the fact that considerable noise is present during the opening and closing operations, since the double lever engages with considerable lateral play with the coupling rail.

Continuing, it should be mentioned that according to other known door drive apparatuses the lateral play of the entrainment mechanism and therefore the formation of noise is prevented in that the entrainment elements, which during elevator travel are located in a retracted position and engage with play with the coupling elements of the shaft doors, at the beginning of the door opening movement are pivoted in such a manner that they contact without play the coupling elements. In such type door actuation or drive the entrainment elements are held by means of a spring for instance in a rocked-out or deflected position and actuated through the agency of a force'locking sliding crank drive possessing a crank wheel movably connected with the crank wheel of a door actuatingthrust crank drive. The construction is designed such that at the beginning of the door opening operation the door actuating-thrust crank drive is located in a dead-center position and the entrainment-sliding crank drive is located almost offset with respect thereto in a position of large piston displacement. Consequently, there is insured that at the beginning of the door opening operation the entrainment elements rapidly engage with the coupling elements, whereas the door practically does not move. Since during normal operation and with the door closed, the door actuating-thrust crank drive is located in a dead-center position, no further locking mechanism is required for the cabin door. However, in order to be able to open the door in the case of power failure there is rovided a spring engaging with the crank wheel and which withdraws the thrust crank drive out of the dead-center position upon absence of the rotational moment of the motor. As a result, when a disturbance or breakdown arises the cabin door can be also opened by a passenger, even if the elevator itself is located between two floors. Bad accidents can therefore occur with this type system.

Additionally, it is to be remarked that an entrainment mechanism is known to the art which consists of an expandable entrainment parallelogram arranged at the cabin door. This expandable entrainment parallelogram embodies two parallel coupling rails hingedly interconnected through the intermediary of two parallel double levers rotatably mounted at the cabin door. Both of the coupling rails are moved away from one another by means of a tension spring engaging with such coupling rails and such coupling rails are pressed together by means of a roller lever moved by electromag netic force. The entrainment parallelogram cooperates with two pins arranged at the shaft door which, when the elevator cabin is located at one of the floors, come to lie between both coupling rails. One such pin is stationarily mounted and the other displaceably mounted. The displaceably mounted pin, during its movement, actuates a shaft door-locking mechanism. For the purpose of locking the cabin door there is provided an electrical door lock which, of course, constitutes an additional expense.

SUMMARY OF THE INVENTION Hence, from what has been stated above, it should be apparent that the prior art is still in need of a door actuating or drive apparatus incorporating a locking mechanism for use with elevators which is not associated with the aforementioned drawbacks and limitations of the prior art constructions. Thus, a primary objective of the present invention is to provide a novel construction of such type door actuating or drive apparatus which effectively and reliably fulfills the existing need in the art and is not associated with the previously mentioned drawbacks and limitations of the state-of-the-art constructions.

Still another and more'specific object of the present invention relates to a new and improved construction of door drive apparatus equipped with a simple and reliably operating locking mechanism allowing for relatively noiseless and uniform movement of the cabin and shaft doors when the elevator cabin is located at the region of the access area of a floor to the elevator and which prevents opening of the cabin door by a passenger when the elevator cabin is located outside of this region.

Yet a further significant object of the present invention relates to a new and improved construction of door drive apparatus equipped with a locking mechanism for elevators or the like which is relatively simple in construction, extremely reliable inoperation, not readily subject to breakdown, requires a minimum of maintenance and servicing, and permits opening of the elevator cabin and shaft doors only when the elevator cabin is located at the region of the level of a floor of the building permitting normal access to the cabin while preventing opening of the cabin door by a passenger when the cabin is located outside of this elevator cabin access region.

Now, in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the door actuating or drive apparatus equipped with a locking mechanism for use with elevators and as contemplated by this invention embodies a blocking or locking lever connected for movement with a known entrainment parallelogram mounted at the cabin door and forming the entrainment means of the coupling mechanism. The entrainment parallelogram can be actuated by an actuation mechanism against spring force and for the purpose of coupling the elevator shaft door cooperates with at least one pin member secured to such elevator shaft door. The blocking lever is pivoted or deflected out along a path of movement described or determined by the door movement during such time as the entrainmerit parallelogram moves between an actuated position until reaching a non-actuated position limited by contact with the pin member. This path of movement is located outside of the effective range of a stop member secured to the elevator cabin. Furthermore, when such blocking lever is deflected-out into a loaded nonactuated position of the entrainment parallelogram past the position limited by the pin member such blocking lever is located in a path of movement disposed within the effective range of the stop member secured to the elevator cabin.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. I is a front view of a preferred constructional embodiment of inventive door actuating or drive apparatus equipped with a bipartite centrally-opening elevator cabin door;

FIG. 2 is a plan view of the door actuating mechanism of FIG. 1 together with an elevator shaft door;

FIG. 3 is an enlarged fragmentary view illustrating details of the entrainment parallelogram in its collapsed or pressed-together position;

FIG. 4 is a view similar to FIG. 3, but this time showing the entrainment parallelogram in a limited expanded position; and

FIG. 5 is a view similar to FIG. I, but illustrating the entrainment parallelogram in its extreme expanded or enlarged position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to the drawings, it is to be understood that there is illustrated therein sufficient constructional details of the inventive door actuating or drive apparatus equipped with a locking mechanism as used for elevators or lifts so as to enable one skilled in the art to fully understand the underlying concepts of this development. Turning attention therefore now more specifically to FIGS. 1 and 2, it is to be understood that reference character 1 designates a conventional elevator cabin, the access opening 1.! of which can be closed by a bipartite central-opening cabin door arrangement 2 embodying both of the door wings or components 2.1 or 2.2. A support plate 3 is secured to the elevator cabin 1 above the cabin door arrangement 2, the lower portion of this support plate being constructed to provide a traveling rail or track 3.1. The door portions 2.1 and 2.2 are displaceably suspended and guided at such traveling rail or track 3.1 through the agency of traveling rollers 2.12 and 2.22.. These traveling rollers are supported by roller mounts 2.11 and 2.21 respectively, arranged at the door wings or portions 2.1 and 2.2 respectively. In order to prevent inadvertent derailing of the traveling rollers 2.12 and 2.22 the vertical degree of freedom of movement thereof in the upward direction of such rollers is delimited by a rail 3.2 secured to the support plate 3.

The upper edgeof the support plate 3 is equipped with a right-angled offset portion 3.3 upon which there are mounted a suitable electric motor 4 and speed reduction drive 5. In the embodiment under consideration the speed reduction drive or step-down drive 5 consists of a two-stage belt drive, by means of which the electric motor 4 drives a crank wheel 6 of a push or thrust crank drive 6 to 1 1 for controlling door movement, crank wheel 6 being mounted at support plate 3.

A double-arm crank lever 7 is connected with the crank wheel 6, this crank lever '7 possessing a pivot point 7.1, and the crank arms 7.2 and 7.3 of which are each equipped at their respective ends with a respective pivot or hinge point 7.21 and 7.31. At these hinge points 7.21 and 7.31 there is mounted the one end of a respective push or thrust rod 8 and 9 respectively, as

shown. The push rod 8 is hingedly connected at its other end with a pivot or hinge point 8.1 of an extended arm 10 secured to the door portion 2.1, whereas the push rod 9 is hingedly connected with a pivot or hinge point 9.1 of an extended arm 11 secured to the other door portion 2.2. The thrust crank drive 6-11 is located in a dead-center position when the cabin door arrangement 2 is closed, that is to say, when the pivot points 7.21, 7.31, 8.1 and 9.1 together with the pivot point 7.1 of the crank lever 7 and the crank wheel 6 are located along a straight line. In this position a cam 6.1 secured to the crank wheel 6 bears against a stop or impact member 3.4 connected with the support plate 3.

At each floor or storey serviced by the elevator cabin 1 there is located a bipartite, centrally-opening elevator shaft door 12 which is situated opposite the cabin door arrangement 2, as best recognized by referring to FIG. 2. This elevator shaft door 12 closes an access opening 13.1 at the elevator shaft wall 13. Shaft door 12 is composed of the shaft door portions or wings 12.1 and 12.2. Now for movement of the elevator shaft door 12 both of the door portions 12.1 and 12.2 are force-lockingly connected by means of a respective coupling mechanism with the oppositely situated door portions 2.1 and 2.2 of the elevator cabin door arrangement 2. Since these coupling mechanisms are essentially identical the description of one should suffice. Thus, each coupling mechanism will be understood to embody an entrainment parallelogram 14 arranged at the associated door portions 2.1 and 2.2 of the cabin door arrangement 2. Entrainment parallelogram 14- is expandable under spring tension and actuatable by means of an actuation mechanism to be considered more fully hereinafter. Further, the entrainment parallelogram 14 engages be tween two pins 15 and their rollers 15.1, which pins are secured to the door portions 12.1 and 12.2 of the elevator shaft door 12. Additionally, the entrainment parallelogram 14 possesses two coupling rails 14.1 which are articulated with one another by means of two double levers 14.2 pivotably mounted at the cabin door portions 2.1 and 2.2 respectively. The coupling rails 14.1 are constructed as so-called sliding curves having bevelled or inclined portions 14.11 at both ends.

A tension spring 14.3 engaging with one of the double levers 14.2 and one of the coupling rails 14.1 serves to spread or expand the entrainment parallelogram 14. The actuation mechanism, which compresses together the entrainment parallelogram 14 against the spring force, is a force-locking sliding crank drive 17 to 19 which is positively or form-lockingly connected with the door actuatingor door drivecrank wheel 6. This sliding crank drive 17 to 19 embodies an actuation rail 13 hingedly displaceably mounted by means of two levers 17 at the support plate 3, the actuation rail 18 being actuated by means of a roller lever 19 secured to the crank wheel 6 and such actuation of rail 18 being against the force of a tension spring 20 arranged between one of the levers 17 and the support plate 3. Actuation of the entrainment parallelogram 14 occurs through the agency of a roller lever 14.4 secured to such entrainment parallelogram. A blocking or locking lever 21 is connected for movement with the entrainment parallelogram 14, this blocking lever cooperating with a stop 22 attached to the support plate 3.

The described door drive apparatus functions in the following manner:

The door actuating or drive apparatus assumes the position depicted in FIG. 1 during travel of the elevator cabin 1. The electric motor 4 is switched-in to rotate in counterclockwise direction and produces a rotational moment serving to retain the thrust crank drive 6 to 11 in dead-center position during which time the cam 6.1 of the crank wheel 6 bears against the stop or impact 3.4. This dead-center position insures that the cabin door arrangement 2 will be maintained closed and cannot be opened by the passengers. The sliding crank drive 17 to 19 thus assumes a position of large displacement and by means of the actuation rail 18 and through the agency of the roller lever 14.4 retains each entrainment parallelogram 14 in its collapsed or pressed together position as depicted in FIG. 3. In this position the blocking or locking lever 21 is deflected or pivoted upwardly. At such time as the elevator cabin 1 travels past a shaft door the entrainment parallelogram moves with play between the pins 15 and rollers 15.1 of the shaft door 12.

As the elevator cabin 1 approaches a desired floor or storey level, then, the electric motor 4 is switched-in so as to rotate in the opposite direction, switching-in of the electric motor 4 occurring approximately 25 cm. prior to the time that the elevator cabin 1 and bottom of the relevant floor or storey are level or flush with one another. Since during such time as the cabin door arrangement 2 is closed the thrust crank drive 6 to 11 is located in dead-center position and the sliding crank drive 17 to 19 is located in a position of large displacement, it should be apparent that during the subsequent rotation of the crank wheel 6 in clockwise direction the entrainment parallelogram 14 is initially expanded or spread very rapidly, whereas the elevator door portions 2.1 and 2.2, as a practical matter, do not experience any movement. Consequently, the entrainment parallelogram 14 travels between the associated pins 15 of the elevator shaft door 12, the coupling rails 14.1 coming to bear against the shaft door. Hence, the entrainment parallelogram 14 is located in an expanded or spread position, as depicted in FIG. d, and is bounded by the pins 15. The elevator shaft door 12 is thus positively or form-lockingly coupled without play with the elevator cabin door arrangement 2, so that during further rotation of the crank wheel 6 there occurs a uniform noiseless opening of both doors 2 and 12. in this limited expanded position of the entrainment parallelogram 14 the blocking lever 21 is rocked into a position where it moves without contact above and past the stop or stop member 22 during the door opening operation.

Assuming now that a defect, for instance power failure occurs, so that the elevator remains standing at some random location, then, the thrust crank drive 6 to 11, upon disappearance of the rotational moment of the electric motor 4, will be moved out of the deadcenter position under the action of the spring force of the tension spring 14.3 of the entrainment parallelogram 14 effective via the roller lever 14.4 and the slifing crank drive 17 to 19. If the elevator cabin 1 is located coincidentally at the region of an elevator shaft door 12, then, the spreading or expanding movement of the entrainment parallelogram 1 1 is again limited by the pins or pin members 15 of the shaft door 12. The elevator cabin door 2 together with the therewith coupled shaft door 12 can be manually opened by a passenger since the blocking lever 21 during the limited expanded position of the entrainment parallelogram 14! is disposed outside of the effective region of the stop 22.

On the other hand, if it is assumed that power failure occurs during such time that the elevator cabin 1 comes to stand-still externally of the region of a shaft door 12, then, during movement of the thrust crank drive 6 to 11 out of the dead-center position the en trainment parallelogram 14 under the influence of the tension spring 14.3 will spread to assume the extreme expanded position of HG. 5. In so doing, the blocking lever 21 assumes a pivoted position where it, upon opening the cabin door arrangment 2 even through a very small displacement opening path, bears against the stop or impact member 22. Hence, during such time as the elevator cabin 1 is located outside of the region of an elevator shaft door 12 the elevator cabin door arrangement 2 importantly cannot be opened by a passenger. Hence, the elevator cabin 1 must be brought by means of outside assistance to the region of an elevator shaft door 12. By virtue of the advantageous design of the coupling rails 14.1 and slide or guide curves 14.11 the entrainment parallelogram 14- also can be introduced between the pins 15 of the elevator shaft door 12 in this extreme spread position. Consequently, the entrainment parallelogram 14 will be returned back to the above-considered limited spread position, whereby the blocking lever 21 again is rocked-out of the effective range of the stop or impact member 22, and the doors 2 and 12 can be manually opened without difficulty from the side of the cabin or the relevant building floor.

The invention is not limited to the illustrated embodiment, and in fact various modifications and changes can be made without departing from the spirit and scope of the teachings of this invention. Thus, for instance, the inventive embodiment can be readily employed for singleor telescopicsliding doors. Furthermore, it is within the contemplation of the teachings of this invention to use differently operating entrainment parallelograms, such as, for instance, a parallelogram which is collapsed or pressed together by means of a spring and spread by means of an actuation mechanism and which, for instance, cooperates with a pin which can be introduced between the coupling rails.

While there is shown and descirbed present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly,

What is claimed is: l

l. A door actuating apparatus for elevators, wherein an elevator cabin door is positively connected at the region of the floor ofa building by a coupling mechanism with an elevator shaft door located at such building floor, said elevator cabin door being movable through the agency of a thrust crank drive located in a deadcenter position when the elevator cabin door is closed, said thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of speed reduction means, the improvement comprising said coupling mechanism incorporating an entrainment parallelogram forming the entrainment member of said coupling mechanism, means mounting said entrainment parallelogram at the elevator cabin door, an actuation mechanism for actuating said entrainment parallelogram, at least one pin member secured to the elevator shaft door at a location externally of said entrainment parallelogram, said entrainment parallelogram cooperating with said pin member for coupling said elevator shaft door with said elevator cabin door, a blocking lever connected for movement with said entrainment parallelogram, stop means secured to the elevator cabin and cooperating with said blocking lever to prevent opening of the elevator cabin door when said parallelogram has opened past the point of contact with said pin member and permitting opening of said elevator cabin door when said parallelogram has opened to the point of contacting said pin member.

2. A door actuating apparatus equipped with a locking mechanism for elevators, wherein an elevator cabin door is positively connected at the region of the floor of a building by a coupling mechanism with an elevator shaft door located at such building floor, said elevator cabin door being movable through the agency of a thrust crank drive located in a dead-center position when the elevator cabin door is closed, said thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of speed reduction means, the improvement comprising said coupling mechanism incorporating as entrainment parallelogram forming the entrainment member of said coupling mechanism, means mounting said entrainment parallelogram at the elevator cabin door, spring means for loading said entrainment parallelogram, an actuation mechanism for actuating said entrainment parallelogram against the spring force of said spring means, at least one pin member secured to the elevator shaft door, said entrainment parallelogram cooperating with said pin member for coupling said elevator shaft door with said elevator cabin door, a blocking lever connected for movement with said entrainment parallelogram, a stop member secured to the elevator cabin and cooperating with said blocking lever to prevent opening of the elevator cabin door when said blocking lever is located within the effective range of said stop member and permitting opening of said elevator cabin door when said blocking lever is located outside of the effective range of said stop member, said blocking lever being pivoted through a path of movement described by the movement of the elevator cabin door during movement of said entrainment parallelogram from its actuated position until reaching a non-actuated position where said entrainment parallelogram contacts said pin member, said pathof movement of said blocking lever being located outside of the effective range of said stop member, to thereby permit opening of the elevator cabin door, said blocking lever being located within the effective range of said stop member when said entrainment parallelogram is deflected through a path of movement extending past said pin member, so that said blocking lever in conjunction with said stop member prevents opening of said elevator cabin door.

3. The door actuated mechanism as defined in claim 2, wherein said entrainment parallelogram comprises two substantially vertically extending coupling rails and two double levers, means mounting said two double levers at said elevator cabin door, said two double levers pivotably interconnecting said coupling rails with one another, said spring means comprising a tension spring for urging said entrainment parallelogram to spread under the action of its spring force, means for connecting said actuation mechanism with the thrust crank drive, said actuation mechanism compressing together said tension spring at the end of the closing operation of said elevator cabin door.

4. The door actuating mechanism as defined in claim 3, wherein said actuation mechanism comprises a sliding crank drive, means for connecting said sliding crank drive with said crank wheel of said thrust crank drive, said sliding crank drive being located in a position of large displacement when the elevator cabin door is closed.

5. The door actuating mechanism as defined in claim 3, further including a pair of said pin members secured to each elevator shaft door, said entrainment parallelogram being in a collapsed condition under the influence of said actuation mechanism when said elevator cabin door is closed and engaging with play between said two pin members at the region of the elevator shaft door in such collapsed condition.

6. The door actuating mechanism as defined in claim 3, further including a pair of said pin members secured to each elevator shaft door, said two substantially vertically extending coupling rails defining slide curves and being provided at each end with bevelled portions facilitating introduction of the entrainment parallelogram between said pin members even when said entrainment parallelogram is in its maximum spread position.

7. The combination with an elevator cabin movable in an elevator shaft of a building between various floors thereof, said elevator cabin having an elevator cabin door arrangement and said elevator shaft having a shaft door arrangement at each floor of the building, of a door actuating apparatus for the elevator cabin door arrangement and shaft door arrangements, said door actuating apparatus comprising a coupling mechanism for positively connecting the elevator cabin door arrangement with the associated elevator shaft door arrangement of the building floor at which the elevator cabin stops when such elevator cabin is located at the region of such building floor, drive means for operably moving said elevator cabin door arrangement, said coupling mechanism embodying at least one expandable entrainment parallelogram constituting the entrainment member of said coupling mechanism, means for mounting said entrainment parallelogram at the elevator cabin door arrangement, an actuation mechanism for actuating said expandable entrainment parallelogram, at least one member secured to said elevator shaft door arrangement, said entrainment parallelogram cooperating with said at least one member for coupling said elevator shaft door arrangement of the associated floor with said elevator cabin door arrangev ment, a blocking lever connected for movement with said entrainment parallelogram for blocking movement of at least one of said door arrangements, a stop member cooperating with said blocking lever in a given position thereof for blocking opening of at least said one door arrangement, said entrainment parallelogram being movable between a collapsed position and an essentially fully expanded position, said blocking lever being disposed outside of the effective range of said stop member during such time as said entrainment parallelogram moves between said collapsed position and a partially expanded position, to permit opening both said elevator cabin door arrangement and the associated elevator shaft door arrangement, said blocking lever being located in the effective range of said stop member in a position for abutting against said stop member when said entrainment parallelogram assumes it fully expanded position, whereby said blocking lever in conjunction with said stop member prevents opening of said at least one door arrangement. 

1. A door actuating apparatus for elevators, wherein an elevator cabin door is positively connected at the region of the floor of a building by a coupling mechanism with an elevator shaft door located at such building floor, said elevator cabin door being movable through the agency of a thrust crank drive located in a dead-center position when the elevator cabin door is closed, said thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of speed reduction means, the improvement comprising said coupling mechanism incorporating an entrainment parallelogram forming the entrainment member of said coupling mechanism, means mounting said entrainment parallelogram at the elevator cabin door, an actuation mechanism for actuating said entrainment parallelogram, at least one pin member secured to the elevator shaft door at a location externally of said entrainment parallelogram, said entrainment parallelogram cooperating with said pin member for coupling said elevator shaft door with said elevator cabin door, a blocking lever connected for movement with said entrainment parallelogram, stop means secured to the elevator cabin and cooperating with said blocking lever to prevent opening of the elevator cabin door when said parallelogram has opened past the point of contact with said pin member and permitting opening of said elevator cabin door when said parallelogram has opened to the point of contacting said pin member.
 2. A door actuating apparatus equipped with a locking mechanism for elevators, wherein an elevator cabin door is positively connected at the region of the floor of a building by a coupling mechanism with an elevator shaft door located at such building floor, said elevator cabin door being movable through the agency of a thrust crank drive located in a dead-center position when the elevator cabin door is closed, said thrust crank drive possessing a crank wheel driven by a motor arranged at the elevator cabin through the agency of speed reduction means, the improvement comprising said coupling mechanism incorporating as entrainment parallelogram forming the entrainment member of said coupling mechanism, means mounting said entrainment parallelogram at the elevator cabin door, spring means for loading said entrainment parallelogram, an actuation mechanism for actuating said entrainment parallelogram against the spring force of said spring means, at least one pin member secured to the elevator shaft door, said entrainment parallelogram cooperating with said pin member for coupling said elevator shaft door with said elevator cabin door, a blocking lever connected for movement with said entrainment parallelogram, a stop member secured to the elevator cabin and cooperating with said blocking lever to prevent opening of the elevator cabin door when said blocking lever is located within the effectiVe range of said stop member and permitting opening of said elevator cabin door when said blocking lever is located outside of the effective range of said stop member, said blocking lever being pivoted through a path of movement described by the movement of the elevator cabin door during movement of said entrainment parallelogram from its actuated position until reaching a non-actuated position where said entrainment parallelogram contacts said pin member, said path of movement of said blocking lever being located outside of the effective range of said stop member, to thereby permit opening of the elevator cabin door, said blocking lever being located within the effective range of said stop member when said entrainment parallelogram is deflected through a path of movement extending past said pin member, so that said blocking lever in conjunction with said stop member prevents opening of said elevator cabin door.
 3. The door actuated mechanism as defined in claim 2, wherein said entrainment parallelogram comprises two substantially vertically extending coupling rails and two double levers, means mounting said two double levers at said elevator cabin door, said two double levers pivotably interconnecting said coupling rails with one another, said spring means comprising a tension spring for urging said entrainment parallelogram to spread under the action of its spring force, means for connecting said actuation mechanism with the thrust crank drive, said actuation mechanism compressing together said tension spring at the end of the closing operation of said elevator cabin door.
 4. The door actuating mechanism as defined in claim 3, wherein said actuation mechanism comprises a sliding crank drive, means for connecting said sliding crank drive with said crank wheel of said thrust crank drive, said sliding crank drive being located in a position of large displacement when the elevator cabin door is closed.
 5. The door actuating mechanism as defined in claim 3, further including a pair of said pin members secured to each elevator shaft door, said entrainment parallelogram being in a collapsed condition under the influence of said actuation mechanism when said elevator cabin door is closed and engaging with play between said two pin members at the region of the elevator shaft door in such collapsed condition.
 6. The door actuating mechanism as defined in claim 3, further including a pair of said pin members secured to each elevator shaft door, said two substantially vertically extending coupling rails defining slide curves and being provided at each end with bevelled portions facilitating introduction of the entrainment parallelogram between said pin members even when said entrainment parallelogram is in its maximum spread position.
 7. The combination with an elevator cabin movable in an elevator shaft of a building between various floors thereof, said elevator cabin having an elevator cabin door arrangement and said elevator shaft having a shaft door arrangement at each floor of the building, of a door actuating apparatus for the elevator cabin door arrangement and shaft door arrangements, said door actuating apparatus comprising a coupling mechanism for positively connecting the elevator cabin door arrangement with the associated elevator shaft door arrangement of the building floor at which the elevator cabin stops when such elevator cabin is located at the region of such building floor, drive means for operably moving said elevator cabin door arrangement, said coupling mechanism embodying at least one expandable entrainment parallelogram constituting the entrainment member of said coupling mechanism, means for mounting said entrainment parallelogram at the elevator cabin door arrangement, an actuation mechanism for actuating said expandable entrainment parallelogram, at least one member secured to said elevator shaft door arrangement, said entrainment parallelogram cooperating with said at least one member for coupling said elevator shaft door arrangement of the aSsociated floor with said elevator cabin door arrangement, a blocking lever connected for movement with said entrainment parallelogram for blocking movement of at least one of said door arrangements, a stop member cooperating with said blocking lever in a given position thereof for blocking opening of at least said one door arrangement, said entrainment parallelogram being movable between a collapsed position and an essentially fully expanded position, said blocking lever being disposed outside of the effective range of said stop member during such time as said entrainment parallelogram moves between said collapsed position and a partially expanded position, to permit opening both said elevator cabin door arrangement and the associated elevator shaft door arrangement, said blocking lever being located in the effective range of said stop member in a position for abutting against said stop member when said entrainment parallelogram assumes it fully expanded position, whereby said blocking lever in conjunction with said stop member prevents opening of said at least one door arrangement. 